1. Field of the Invention
The field of the present invention relates to a method and an apparatus for carrying out a burning test on a test piece.
2. Background
Materials are working resources of a purely substance-like nature that are further processed as objects of work in production processes and are subsumed in the respective end products. They are generally solid bodies, such as for instance metals or plastics. Before the end products produced from corresponding materials can be sold by the manufacturer, the end products must undergo a large number of tests, to rule out possible hazards arising from the product for a product user and accordingly also minimize the manufacturer's risk of liability. Therefore, end products are, for example, subjected to a fire test, to be able to assess the end product with regard to the fire hazard.
Furthermore, the materials used for the manufacture of the end products are subjected to what is known as preselection testing. In preselection testing, it is not that the entire product as such is investigated for its fire hazard, but instead the individual materials that are used for an end product are investigated for their burning properties. Preselection tests on materials are usually performed on test pieces that consist of the material to be tested and have a simple, standardized form, such as for example that of rectangular bars.
For example, European Standard EN 60695-11-10 specifies a test method for assessing the fire hazard of materials. According to one variant of the test method, known as the vertical burning test, a burner is held at a distance of 10 millimeters under a bar-shaped test piece, which is suspended vertically with respect to its longitudinal axis, for two periods of 10 seconds. The flame is in this case set to a nominal value of 50 watts. After completion of each instance of flame exposure of the test piece, what is known as the burning time of the test piece is determined, and then the test piece is categorized on the basis of the burning times determined in various categories that are specified more precisely in the aforementioned standard.
According to the prior art, methods for fire testing, such as for example for carrying out the method described in the aforementioned European standard, are carried out by operating personnel, who, for the flame exposure, hold a burner at the distances set out in the respective standard from the test piece for the times specified in the standard. However, it is clear that a test method carried out by personnel is also prone to subjective, personal influences. For example, the distance between the burner and the test piece will only approximately correspond to the distance that is prescribed in the standard.